Nos. 20743, 20787. Argued September 12, 1967. Decided February 9, 1968. Mr. Jacob B. Davis, Baltimore, Md., with whom Mr. George Cochran Doub, Baltimore, Md., was on the brief, for petitioner in No. 20,743. Mr. Bernard W. Rubenstein, Baltimore, Md., with whom Mr. Jacob J. Edelman, Baltimore, Md., was on the brief, for petitioner in No. 20,787. Mr. Solomon I. Hirsh, Attorney, National Labor Relations Board, with whom Messrs. Arnold Ordman, General Counsel, Dominick L. Manoli, Associate General Counsel